--- zzzz-none-000/linux-3.10.107/include/linux/rmap.h	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/include/linux/rmap.h	2021-02-04 17:41:59.000000000 +0000
@@ -37,6 +37,16 @@
 	atomic_t refcount;
 
 	/*
+	 * Count of child anon_vmas and VMAs which points to this anon_vma.
+	 *
+	 * This counter is used for making decision about reusing anon_vma
+	 * instead of forking new one. See comments in function anon_vma_clone.
+	 */
+	unsigned degree;
+
+	struct anon_vma *parent;	/* Parent of this anon_vma */
+
+	/*
 	 * NOTE: the LSB of the rb_root.rb_node is set by
 	 * mm_take_all_locks() _after_ taking the above lock. So the
 	 * rb_root must only be read/written after taking the above lock
@@ -72,14 +82,16 @@
 };
 
 enum ttu_flags {
-	TTU_UNMAP = 0,			/* unmap mode */
-	TTU_MIGRATION = 1,		/* migration mode */
-	TTU_MUNLOCK = 2,		/* munlock mode */
-	TTU_ACTION_MASK = 0xff,
+	TTU_UNMAP = 1,			/* unmap mode */
+	TTU_MIGRATION = 2,		/* migration mode */
+	TTU_MUNLOCK = 4,		/* munlock mode */
 
 	TTU_IGNORE_MLOCK = (1 << 8),	/* ignore mlock */
 	TTU_IGNORE_ACCESS = (1 << 9),	/* don't age */
 	TTU_IGNORE_HWPOISON = (1 << 10),/* corrupted page is recoverable */
+	TTU_BATCH_FLUSH = (1 << 11),	/* Batch TLB flushes where possible
+					 * and caller guarantees they will
+					 * do a final flush if necessary */
 };
 
 #ifdef CONFIG_MMU
@@ -96,28 +108,6 @@
 		__put_anon_vma(anon_vma);
 }
 
-static inline struct anon_vma *page_anon_vma(struct page *page)
-{
-	if (((unsigned long)page->mapping & PAGE_MAPPING_FLAGS) !=
-					    PAGE_MAPPING_ANON)
-		return NULL;
-	return page_rmapping(page);
-}
-
-static inline void vma_lock_anon_vma(struct vm_area_struct *vma)
-{
-	struct anon_vma *anon_vma = vma->anon_vma;
-	if (anon_vma)
-		down_write(&anon_vma->root->rwsem);
-}
-
-static inline void vma_unlock_anon_vma(struct vm_area_struct *vma)
-{
-	struct anon_vma *anon_vma = vma->anon_vma;
-	if (anon_vma)
-		up_write(&anon_vma->root->rwsem);
-}
-
 static inline void anon_vma_lock_write(struct anon_vma *anon_vma)
 {
 	down_write(&anon_vma->root->rwsem);
@@ -151,7 +141,7 @@
 static inline void anon_vma_merge(struct vm_area_struct *vma,
 				  struct vm_area_struct *next)
 {
-	VM_BUG_ON(vma->anon_vma != next->anon_vma);
+	VM_BUG_ON_VMA(vma->anon_vma != next->anon_vma, vma);
 	unlink_anon_vmas(next);
 }
 
@@ -183,17 +173,13 @@
  */
 int page_referenced(struct page *, int is_locked,
 			struct mem_cgroup *memcg, unsigned long *vm_flags);
-int page_referenced_one(struct page *, struct vm_area_struct *,
-	unsigned long address, unsigned int *mapcount, unsigned long *vm_flags);
 
 #define TTU_ACTION(x) ((x) & TTU_ACTION_MASK)
 
 int try_to_unmap(struct page *, enum ttu_flags flags);
-int try_to_unmap_one(struct page *, struct vm_area_struct *,
-			unsigned long address, enum ttu_flags flags);
 
 /*
- * Called from mm/filemap_xip.c to unmap empty zero page
+ * Used by uprobes to replace a userspace page safely
  */
 pte_t *__page_check_address(struct page *, struct mm_struct *,
 				unsigned long, spinlock_t **, int);
@@ -236,10 +222,24 @@
 int page_mapped_in_vma(struct page *page, struct vm_area_struct *vma);
 
 /*
- * Called by migrate.c to remove migration ptes, but might be used more later.
- */
-int rmap_walk(struct page *page, int (*rmap_one)(struct page *,
-		struct vm_area_struct *, unsigned long, void *), void *arg);
+ * rmap_walk_control: To control rmap traversing for specific needs
+ *
+ * arg: passed to rmap_one() and invalid_vma()
+ * rmap_one: executed on each vma where page is mapped
+ * done: for checking traversing termination condition
+ * anon_lock: for getting anon_lock by optimized way rather than default
+ * invalid_vma: for skipping uninterested vma
+ */
+struct rmap_walk_control {
+	void *arg;
+	int (*rmap_one)(struct page *page, struct vm_area_struct *vma,
+					unsigned long addr, void *arg);
+	int (*done)(struct page *page);
+	struct anon_vma *(*anon_lock)(struct page *page);
+	bool (*invalid_vma)(struct vm_area_struct *vma, void *arg);
+};
+
+int rmap_walk(struct page *page, struct rmap_walk_control *rwc);
 
 #else	/* !CONFIG_MMU */